I've been in a lot of quakes. Sometimes when a 5.5 happens, we stand around the office with a smile remarking "Did you feel that? Not bad.". This one, at 4.5 felt much worse. They say it was near the surface, and therefore was felt more strongly. There was some very sharp movements sideways, north and south, in my home and it felt bad. Nothing fell down.
Back in 1989, during the Loma Prieta quake we had a lot of stuff falling over. My wife and kids were home in SSF while I was on the telephone with my wife, at the office in downtown SF some 15 miles away. She and the kids started screaming on the phone and I was puzzled, then she said "Earthquake!". I didn't feel it downtown until some seconds later as it rolled up the peninsula. Then stuff started falling over in the office. Through my window I saw utility light poles swaying back and forth, and my office had a window into the computer room where I saw mobile racks falling over spilling tape cartridges and data racks moving about. That had a lot of sharp movements, which lasted a real long time. The one last night was just a few seconds. In 1989 at my house, we had a huge expensive narrow vase with tall flowers on a glass table. My wife watched as it bounced around and fell to the floor. Amazingly, it fell upright without breaking. Awesome power in quakes, makes one feel downright puny.
My brother lived in LA and he told me that big earthquakes always happen without warning. You get a big one and then after-shocks but no “pre-shocks”